Spark plug



April 15, 1930. J. P. RITCHEY SPARK PLUG Filed July 28, 1928 J: Pia o/ire.

/ flame/134 Patented Apr. 15, 1930 UNITED STATES JOHN P. RITGHEY, OF WICHITA, KANSAS SPARK PLUG Application filed July 28, 1928. Serial No. 295,944

The present invention is directed to immovements in spark plugs.

The primary object of the invention is to provide a plug having a plurality of spark l gaps so arranged that the sparks will be intensified when occurring in the combustion chamber of the motor.

Another object of the invention is to provide a spark plug provided with a plurality 10 of gaps for producing sparks as the current flows to the main electrode, and gaps for subsequent sparks when the current flows from the main electrode.

With these and other objects in View, this invention resides in the novel features of construction, formation, combination and arrangement of parts to be hereinafter more fully described, claimed and illustrated in the accompanying drawing, in which Figure 1 is a vertical sectional view through the plug.

Figure 2 is a perspective view showing spline of the discs in non-assembled relations 1p.

Figure 3 is a sectional view on line 3-3 of Figure 1.

Referring to the drawing, 1 designates the shell to which is secured the ground electrode 2 as customary, said shell being provided with annularly spaced heat dissipating webs 3.

Mounted in the shell 1 is a body 4 formed from porcelain or other suitable insulating material, said body having annular engagement 5 which seats on the shoulder Got the shell and is held within the shell by the sleeve nut 7 The main electrode 8 extends axially through the body 4: and has its upper ends provided with a threaded extension 8 for threaded engagement in the body, the upper face of said extension being in a plane with the upper end of said body. The body has an annular shoulder 9 upon its upper end, the purpose of which will be later explained.

A brass cap 10 is provided and in this cap is snugly fitted a plurality of mica discs 11 and 12, the former having formed centrally therein openings 13, while the latter are provided with relatively large openings 14 and in which are engaged metallic discs 15. The discs 11 and 12 are preferably cemented to' gether, thus holding the metallic discs 15 firm' ly in place and in spaced relation in order to provide spark gaps 16.

.The cap 10 has carried thereby a threaded shank 17 and upon which is engaged the terminal binding nut 18. In order to hold the cap engaged with the end of the body said cap is crimped, as at 19, intoengagement with the shoulder 9.

Secured in the lower end of the shell 1 is an arm 20, said arm having a horizontally. disposed shaft 21 carried thereby which bridges the lower open end of the shell and has rotatably mounted thereon a porcelain sleeve 22, and bindingly engaged-upon said sleeve is a metallic band electrode 28 which is interposed between the electrode 2 and elec trode 8. Due to the fact that electrode 23 is mterposed between the electrodes 2 and 8 oil cannot reach the electrode 8, consequently protecting the same against fouling and since the electrode 23 can be rotated the same can be cleaned without removing the same from the plug.

It will be apparent that when the current is supplied to the cap 10 that it will pass through said cap and produce sparks successively in the gaps 16 produced between the discs 15. Thus the current will be intensified as it passes into the main electrode 8. Sparks will also occur in the gaps 24 and 25 produced between the electrode 23 and electrodes 2 and 8.

Owing to the fact that the discs 11, 12 and 15 are confined in the cap 10 the same will be protected against moisture or other foreign matter.

As shown six spark gaps are produced and curring in the combustion chamber will be of considerable volume and sharpness, thus assuring efficient ignition of the gas within the compression part of the motor.

From the foregoing, it is thought that the construction, operation and many advantages of the herein described invention will be a parent to those skilled in the art, without urther description and it will be understood that various changes in the size, shape 5 and proportion and minor details of construction, may be resorted to Without departing from the spirit or sacrificing any of the advanmgas of the invention.

What is claimed is 10 1. A spark plug comprising a shell, a body of insulating material therein, a main electrode in the body, a ground electrode carried by the shell, a cap secured to the upper end of the body, a plurality of superposed mica discs 15 confined in the cap and having openings therein, alternate discs having metallic discs in their openings and spaced the thickness of a mica disc to produce spark gaps.

2. A spark plug a shell, a body I of insulating material secured to the shell, a

main electrode carried by the body, a plurality of discs of insulating material mounted a: the body and having openings therein, metallic discs mounted in the openings of al- I tomato discs and spaced to provide spark ga s.

A spark plug comprising a shell, a body of insulating material secured thereto, a main electrode carried by the body, a ground electrode carried b the shell, :1 cap secured to the body and aving a terminal engaging shank carried thereby, a plurality of mica discs and a plurality of metallic discs confined within the cap, the mica discs having openings therein, said metallic discs being maintained in a spaced relation by the mica discsmounted in said openings and to provide a larality of spark gaps.

n testimon wheeof I aflix my signature.

40 J HN P. RITCHEY. [1 5.] 

